双向链表排序

package test;

public class ListSort {

	class Node {
		Node pre, next;
		int value;

		public Node(int value) {
			this.value = value;
		}
	}

	Node head,tail;

	public void add(Node n) {
		
		if(n==null)
			return;

		Node temp = head;

		if (temp == null) {//如果根节点为空 则设为根节点
			head = n;
			tail = n;
		} else {
			while (temp != null) {
				if (n.value > temp.value) {//有位置 则放到节点的前面
					if (temp.pre == null) {
						head = n;
						tail = n;
					} else {
						temp.pre.next = n;
						n.pre = temp.pre;
					}
					temp.pre = n;
					n.next = temp;
					return;
				} else {
					if (temp.next != null) {//没有位置则找下一个节点  如果下一个节点为空 则放入队尾 并结束循环
						temp = temp.next;
					} else {
						temp.next = n;
						n.pre = temp;
						temp = null;
						tail=n;
						
					}
				}
			}
		}

	}



	public void print(int type) {
		
		if(type==1) {
			Node n = head;
			while (n != null) {
				System.out.println(n.value);
				n = n.next;
			}
		}else {
			Node n = tail;
			while (n != null) {
				System.out.println(n.value);
				n = n.pre;
			}
		}
	}

	public void build() {
		int[] arr = ArrCreater.create(10);
		ArrCreater.printArr(arr);
		for (int i : arr) {
			add(new Node(i));
		}
	}

	public static void main(String args[]) {
		ListSort ls = new ListSort();
		ls.build();
		ls.print(1);
		System.out.println("@@@@@@@@@@");
		ls.print(2);
	}
}